Messages in this thread | | | Date | Sun, 17 Oct 2010 19:36:09 +0200 | From | Dan Carpenter <> | Subject | Re: [PATCH 6/8] char: synclink: fix information leak to userland |
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On Sun, Oct 17, 2010 at 07:38:39PM +0400, Vasiliy Kulikov wrote: > On Sun, Oct 17, 2010 at 17:34 +0200, Jiri Slaby wrote: > > On 10/17/2010 04:41 PM, Vasiliy Kulikov wrote: > > > Structure new_line is copied to userland with some padding fields unitialized. > > > It leads to leaking of stack memory. > > > > I think your tool has a bug. I must admit I fail to see the padding > > which would cause leaks. Could you elaborate? > > I didn't use any tool except "grep copy_to_user" :) >
It seems like you should be able to use pahole to make a list of structs with padding and then a checker script to find places where information is leaked.
Also someone complained to me about when I added a memset() in a fast path. The thought was that it might be faster to just initialize it instead like:
struct foo bar = {};
In my case just using the initializer made the code cleaner so I did it, but neither of us actually benchmarked it.
regards, dan carpenter
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